The technology is largely theoretical but would probably work like this: Besides having traditional radios or CD players, cars would also have a Roadcasting feature. When it is turned on, it would search for all the digital playlists being played nearby, probably over some kind of mobile Wi-Fi network, the same kind of technology that allows you to flip open your laptop and check e-mail at a coffee shop or airline terminal.

The Roadcasting screen would show song and DJ names, and music genres, then judge which offerings match your musical tastes. As you selected songs, the software would keep refining and learning about your tendencies, and would use them to find other songs that match them. Other listeners could listen to the same playlist and vote on songs at the same time, influencing what the ad hoc networks played.

The concept sounds intriguing: it would be interesting to see whether / how roadcasting might help form communities among commuters ... and whether it would help reduce road rage. There are alot of important details that would need to be worked out, e.g., an interface that was not too distracting (perhaps speech recognition would help, though the background "noise" generated by the music might be a problem ... unless the system could use some kind of "music-cancelling" filter, which may be possible since it could have direct access to the digital source of the music), a variety of legal issues revolving around digital rights management, and a host of social issues that may impact the acceptance and use of such technology ... many of which would be difficult to identify, much less resolve, in the absence of a deployment. I wonder how much of the burden of technical infrastructure requirements (e.g., WiFi in cars) could be alleviated by the use of short range FM transmitters.

CommuterNews (from the Persuasive Technology Lab at Stanford University):CommuterNews engages the: driver with questions and relevant clips selected from a standard 3-4 minute radio news story. The system keeps track of how many questions have been answered correctly and gives the driver opportunities to earn prizes and compete with other CommuterNews players. The session can be interrupted at any time, but a typical interaction with the prototype (4 news stories, with 4-5 questions per story) approximately correlates to an average commute of 20 minutes.

FolkMusic (by Mikael Wiberg at the Interactive Theory Lab of Umea University):a mobile peer-to-peer entertainment system that builds on the current trends towards: 1) edutainment software, 2) increase in use of peer-to-peer technologies, and, 3) the current trend towards mobile computing solutions. Further on, the research reported in this paper builds on prior research on "folk computing" for which mobile ad-hoc peer-to-peer solutions are a focal concern.

Jukola (by Kenton O'Hara, et al., at the Appliance Studio): a digital jukebox which was tested in Watershed's Café/Bar in Oct 2003. Using wireless technology, handheld iPAQS and touch screens, visitors to the Café/Bar were able to try out Jukola by viewing a selection of nominated tunes, finding out more information about them and submitting their vote to determine the next track. Jukola was networked to allow access over the web to review a history of the music played and for musicians to submit MP3s remotely - providing an opportunity for any unsigned bands out there to upload their own music and put it to the public vote.

Adaptive Radio (by Dennis Chao, et al., at University of New Mexico): a system that selects music to play in a shared environment. Rather than attempting to play the songs that users want to hear, the system avoids playing songs that they do not want to hear. Negative preferences could potentially be applied to information filtering, intelligent environments, and collaborative design.

MusicFX (by me and Ted Anagnost, when we were both at Accenture Technology Labs):an example of an active environment that uses a group preference arbitration system to allow the members of a fitness center to influence, but not directly control, the selection of music in that environment. The system contains a database of members' musical preferences, a badge system for determining who is working out, and a weighted random selection algorithm for selecting music to best suit the group inhabitants at any given time. MusicFX was in daily use in the fitness center at Accenture Technology Park in Northbrook, IL (USA), between November 1997 and December 2001.

Of the many features of MusicFX that people enjoyed, the two most frequent complaint categories involved the abrupt music changes (the system would sometimes change channels mid-song, as people entered or left the fitness center) and the "occasional" exposure to bad music (the price of variety, serendipity and democracy) ... factors that may be exacerbated in a mobile environment such as a car. While people generally enjoyed the increased variety, the most oft-cited advantage was the ability to have some influence over the music in the shared environment of the fitness center. Given that most people have far more control over the music playing in their car, it would be interesting to see whether the increased variety and serendipity offered through Roadcasting would compensate for the loss of control. The biggest factors may well be the communty-oriented issues of contribution and reputation ... factors that would be very difficult to assess without some kind of deployment.